#.PHONY:test #使得test变成伪目标，test命令总是被执行，每次都重新编译，但不建议这么做。
#test:test.o
#	gcc test.o -o test
#test.i:test.c
#	gcc -E test.c -o test.i
#test.s:test.i
#	gcc -S test.i -o test.s
#test.o:test.s
#	gcc -C test.s -o test.o

test:test.c
	@gcc -o $@ $^ #$@ represents the relationship and $^ represents method
	# use @ before the command if you don't want it show in your screen.
	#gcc test.c -o test

.PHONY:clean #usually used it in clean.
clean:
	@rm -f test.i test.s test.o test
